The present invention relates to methods and devices for converting the energy from ocean or water waves to useful energy. More particularly, the present invention relates to the conversion of periodic wave motion present near beaches of the ocean to useful electrical energy.
Since the beginning of time, man has viewed the power of the oceans with awe and has long sought methods for harnessing this power for useful purposes. Perhaps one of the greatest forms of natural energy associated with the oceans is the recurring waves action that define the constantly changing boarders to these massive bodies of water. Powered by gravitational forces of the moon and changing weather conditions of wind, temperature and rain, the ever changing tides and propagation of wave motion across the water surfaces of the earth generate an immeasurable force which continually pounds virtually every exposed shoreline of every continent of the world.
Attempts to tap this source of energy have experienced only nominal success. Whereas development of hydroelectric power sources on rivers has been a simple matter of applying a turbine to a moving stream of water, the capture of water movement of periodic waves has been a formidable challenge. Hundreds of devices have been contrived to directly respond to the ocean movements; however, few have survived the test of general commercial application. Typical approaches to this problem have included the use of tethered paddles, buoys and a myriad of other floating objects designed to move laterally with the currents in a rhythmic pattern, while transferring this energy to a mechanical linkage capable of generating electrical output.
A primary flaw in such systems arises from the surface location, or at least suspended linkage to surface structure, providing a dependence upon lateral interaction of moving mechanical parts with surface wave action to provide the medium of transfer of force from the oceans to a power generator. Such mechanical assemblies are not only expensive, but require regular maintenance and repair due to changing weather conditions at the surface, which are manifest in severe forces capable of crushing the strongest of structures. In addition, the constantly changing tides mandate complex height adjustment mechanisms to adjust to changing water levels. The resulting variations in operating conditions make it difficult to provide a single system that is capable of coping with the multitude of variables which must be satisfied in a surface-linked mechanical system of energy conversion.
What is needed is a power generation system which operates in response to the periodic wave motion of the waters, but in a manner independent from other surface water conditions to produce electrical energy. The system must be economically feasible by favorably balancing cost of energy production versus kilowatt output.
It is an object of the present invention to capture energy from recurring wave motion of water by indirect conversion of vertical motion to electrical power output.
It is a further object of the invention generate electrical power in response to changing weights of water over a fixed, submerged surface as a function of time.
Yet another object of this invention is to develop conversion of wave motion to electrical power without depending upon moving objects suspended within the water.
A still further object of this invention is the conversion of tidal energy and recurring wave motion to electrical energy indirectly based on changes in weight of the water as it flows onto and recedes from the beach in a recurring manner.
These and other objects are realized in a power transfer system which includes a, pressure transducer positioned at the ocean floor and under a location of wave movement configured for (i) registering changes in height of water in alternating crests and troughs above the pressure transducer and (ii) providing an electrical power output at the transducer corresponding to changes in force associated with the changes in the height of water. Other benefits and features will be apparent to those skilled in the art, based on the following detailed description, taken in combination with the accompanying drawings.
FIG. 1 graphically represents an array of pressure transducers coupled to a battery storage system, including access to utility power transfer lines.
FIG. 2 represents a cross section of ocean beach which has been modified with a wave energy transfer system as shown in FIG. 1.
FIG. 3 graphically illustrates a process for laying a grid of pressure transducers within a fluidized trench under the beach area of an ocean water source.
FIG. 4 illustrates a mat of transducers secured to a rigid grid support for placement at the ocean floor, under several feet of sand, with a connecting wire for attachment to a power storage bank.
FIG. 5 shows another embodiment of the present invention wherein electricity is developed by the relative movement of a magnet with respect to a coil, biased to a return position by a spring.
FIG. 6 is a cross-section of FIG. 5, taken along the lines 6xe2x80x946.
FIG. 7 represents an additional embodiment using a piston configuration with leveraged force for conversion of linear motion to rotary motion in combination with a generator.
FIG. 8 shows a perspective view of a billows device coupled to a rotary power conversion generator.
FIG. 9 depicts a graphical cross-section of a lever arm powered by a billows device and coupled to linear electrical generator.
FIG. 10 illustrates an additional embodiment of-a magnet/coil generator in a mat.
FIG. 11 shows a variation of the magnet/coil combination.